Someone who can maintain an orderly, outward social appearance while their personal life has devolved into complete chaos due to over-drinking. Their friends and family are often impressed with their achievements, while the alcoholic knows that their drinking has lead to a full-blown loss of control and that it is just a matter of time until their behavior blows up in their face. In a bad way.
Emelio's friends/family: " Emelio is about to graduate med school. We are so proud. We only wish we could accomplish as much".

Emelio: "I am a functional alcoholic. Everyone I know thinks I'm doing great but in reality my brain has turned to slush. I can't believe I BS'd my way through med school and got a 3.8 GP because I don't remember any of it. I can't believe I'm almost 30 and have somehow avoided getting a DUI thus far. Everyone thinks I'm so great, but in reality, I'm totally fucking dangerous but I just haven't been caught yet. It's all catching up with me though. It's only a matter of time until I do something really stupid and everyone will realize what a fuck-up I truly am.
by ???s upon ???s September 1, 2016
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When one can be drunk every night and still be completely function able the next day
Nate went out every night this week and got totally shit faced. He still got to work the next morning at 8... He's a functioning alcoholic
by Tater tot 5190 July 1, 2014
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a worthless yet admirable person who can drink everynight and still pull good grades in college or act as a normal person in a work environment.
that bitch drinks every f'n night and made a better grade than me on the test.

Or:
i saw that douche torn up last night and today he acts like mr. super employee. wtf?
by d March 31, 2005
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An excuse term alcoholics use to justify their continued self-destruction.
Joe: "Wow, James is drinking and it's only 7 AM."
Mike: "He's a high functioning alcoholic. He says he needs it to function."
Joe: "So he's a severe alcoholic who needs help then."
by Super Thicc November 22, 2020
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Someone who always drinks too much and whose life is falling apart because of it. ... Some people seem to be just fine even though they abuse alcohol. Experts call these people “functional” or “high-functioning" alcoholics."
Even though we never see Sarah sober, it doesn't get in the way of her life.

Sarah being a high functioning alcoholic has a sucessful life, job, and family.
by Kenztenz July 31, 2017
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